Mission: Slessor Grounding Zone / Lake IS-2

Priority: High

 

This new flight is designed to map portions of the Slessor and Bailey Glaciers, along ICESat-2 ground tracks. For these tracks, we specifically target the strong beam of the beam pairs, which in the case of this flight are all center beam pairs and TEP.

 

This mission was the best available option, based on MODIS imagery and multiple model forecasts. Nothing farther west was viable, and only the Stancomb-Willis region could have been considered. At the beginning of the mission, we collected a 1500' ramp pass across the PUQ runway. We passed over the Antarctic Peninsula, but did not spot the A-68 iceberg due to clouds. About halfway across the Weddell Sea, the clouds cleared and extensive sea ice with intermittent icebergs were visible. During the survey, we saw blowing snow and impressively glazed surfaces within the windswept trough of Slessor Glacier, especially  during the downstreammost across-flow lines, along with substantial cross-winds but minimal turbulence. Our first flight proceeded exactly as planned, and no major instrument issues were reported. It took about 15 minutes the beginning of the survey to get the IR sensor on the ATM T7 synched up with the laser returns, an adjustment that should not have to be repeated, but otherwise altimetry collection was 100%. MCoRDS ice-bed reflections were regularly visible, with some exceptions over regions of extensive surface crevassing.

 

Attached images:

1. Map of today's mission (John Sonntag / NASA)

2. Coastal polynya near the Filchner Ice Shelf (John Sonntag / NASA)

3. Snow blowing off the Filchner Ice Shelf into the adjacent ocean (Linette Boisvert / NASA)

4. Crew in the DC-8 cockpit during a turn (Linette Boisvert / NASA)

5. Blue ice near Slessor Glacier (Jeremy Harbeck / NASA)

6. The Shackleton Range at sunset with snow blowing off the ridges (Michael Studinger / NASA)